Ski binding

ABSTRACT

A ski binding consisting of a toe piece whose boot-engaging lug rises to release the boot when the toe piece has rotated under stress.

United States Patent Ulbrich Nov. 5, 1974 SKI BlNDlNG I [56] References Cited [75] inventor: Konrad A. Ulbrich, Wellesley, Mass. UNITED STATES PATENTS 3,000,644 9/1961 Beyl 280/1135 T [73] Asslgne' ggz' zg g' fizzg west 3,l88,l()4 6/l965 Magnin 280/! 1.35 T 3.201.140 8/1965 Marker 280/l L35 T [22] Filed: Mar. 22, 1973 Primary Examiner-Robert R. Song [21] Appl' 343976 Attorney, Agent, or FirmN0rman S. Blodgett; Gerry Related US. Application Data A. Biodgett [63] Continuation of Ser. No 161.188, July 9, I97].

abandoned [57] ABSTRACT A ski binding consisting of a toe piece whose boot- (g1 28221313970? engaging lug rises to release the boot when the we c t 58 Field of Search 280/1135 T p'ece has mated under 5 5 Claims, 3 Drawing Figures PAIENIEIJNHY 5 m4 INVENTOR.

KONRAD A. ULBR/CH ATTOREY SKI BINDING This is a continuation, of application Ser. No. 161,188 filed July 9, 1971, now abandoned.

BACKGROUND OF THE INVENTION Ski bindings usually consist of a toe piece and a heel piece mounted on the ski and engaging, respectively, the toe and the heel of a ski boot. Modern ski bindings are constructed to hold the ski boot firmly on the ski for accurate control of edging and turning, but to be capable of releasing the boot when more than a predetermined force is transmitted from the ski to the leg of the skier through the binding. At such a time, the binding releases" and prevents the skiers leg from being damaged. Most toe pieces are swingably mounted so that, when the force is very great, the toe of the boot is allowed to move sideways on the ski and the boot moves out of the space between the toe piece and the heel piece. Although toe pieces constructed in this way have been considered adequate in the past, it has been found that the sideways movement is inhibited by the friction on the sole of the ski boot by the ski on one side and the toe piece lug on the other. When this friction prevents the boot from moving sideways relative to the ski and releasing, the skier is liable to be hurt. At the same time, it is necessary that the toe piece lug press tightly on the upper surface of the ski boot sole, so that movements of the boot by the. skier bring about movements of the skis for proper skiing technique, so, the answer to the problem is not simply to loosen the lug. These and other difiiculties experienced with the prior art devices have been obviated in a novel manner by the present invention.

It is, therefore, an outstanding object of the invention to provide a ski binding toe piece in which the lug lifts when the toe piece turns.

Another object of this invention is the provision of a toe piece in which friction on the ski boot sole is substantially reduced when stress causes the toe piece and the boot to turn laterally.

A further object of the present invention is the provision of a ski binding toe piece in which the release characteristics are the same, irrespective of the condition of the ski boot sole, i.e., whether the sole is dry or wet, new or old, smooth or rough, or whether or not it is covered with ice.

It is another object of the instant invention to provide a swivel-type toe piece which is simple in construction, inexpensive to manufacture, and which is capable of a long life of useful service.

A still further object of the invention is the provision of a swivel-type toe piece which has no intricate parts to become fouled by snow and ice and water.

With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the cimbination of parts set forth in the specification and covered by the claims appended hereto.

SUMMARY OF THE INVENTION In general, the invention consists of a ski binding having a base adapted to be fastened to the upper surface of the ski and a pivot shaft extending vertically from the base. A main body is pivotally mounted on the shaft and has a rearwardly-directed lug adapted in its operative position to engage the sole of a ski boot. A cam means is interposed between the base and the main body to cause the main body and lug to rise vertically when they rotate together about the shaft axis in either direction from said operative position.

BRIEF DESCRIPTION OF THE DRAWINGS The character of the invention, however, may be best understood by reference to one of its structural forms, as illustrated by the accompanying drawings, in which:

FIG. 1 is a perspective view of a ski binding incorporating the principles of the present invention,

FIG. 2 is a sectional view of the invention taken on the line II-II of FIG. I, and

FIG. 3 is a sectional view of the invention taken on the line Ill--Ill of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the description which follows, the expressions longitudinal, transverse," rear," front, and the like refer to those directions as normally applied to a ski.

Referring first to FIG. 1, it can be seen that the ski binding, indicated generally by the reference numeral 10, consists of a base 11 adapted to be mounted on the upper surface of a ski and a main body 12 pivotally mounted above the base. The main body 12 is provided with a vertically-adjustable element 13 having rearwardly-directed lugs 14 and 15, whose undersurfaces are adapted to engage the upper surface of the sole of the toe of a ski boot resting on the ski. The element 13 is suitably guided for vertical sliding movement on the rearward portion of the main body 12 and a screw 16 is rotatably mounted in the main body to bring about the adjustment of the element 13. Also mounted on the top of the main body is a large screw element 17 which is concentric with the axis of pivotal motion of the main body 12 relative to the base 11.

Referring now to FIG. 2, it can be seen that a vertical shaft 18 is fixed to the base 11 and extends upwardly into a bore 19 extending through the main body 12. An upper portion 21 of the shaft 18 is threaded and engages a similar threaded bore 22 formed in the screw member 17. The bore 19 in the main body is provided with a long counterbore 23 in its upper part into which the outside diameter of the screw 17 fits snugly. In the space between a reduced lower portion of the screw 17 and the surface of the counterbore 23 is located a coil spring 24. The amount of threaded engagement between the screw l7 and the upper part 21 of the shaft 19 controls the amount of compression of the spring 24. A cam means 25 extends between the main body 12 and the base 11 in the vicinity of the shaft 19 to cause the main body and the lug element 13 to rise vertically when they rotate together about the shaft axis in either direction from an intermediate operative position shown in the drawings. The cam means 25 consists of a V-shaped cam 26 extending downwardly from the undersurface of the main body 12 and a V-shaped recess 27 formed in the upper surface of the base 11. The cam 26 and the recess 27 are located in the centerline of the ski binding extending in a rearward direction from the shaft.

FIG. 3 shows the manner in which the cam 26 is operative in its recess 27. An exactly similar cam and recess are fonned diametrically opposite the axis of the shaft l9 and are located in the forward part of the ski bindmg.

The operation of the invention will now be readily understood in view of the above description. The ski binding is fastened as a toe piece to the upper surface of the ski along with the heel piece. The toe of the ski boot is inserted into the binding with the upper surface of the boot sole engaging the undersurfaces of the lugs 14 and 15. Then the heel piece is actuated in the usual way to clamp the heel of the boot and thrust it forward tightly into the toe piece. The toe piece and the heel piece hold the boot firmly to the ski to permit close control of edging and turning. However, if an accident occurs, large forces can be transmitted from the ski to the skiers leg; the most common force that occurs is torsional, i.e., tending to twist the skiers leg about its longitudinal axis. When this force exceeds a predetermined value, as determined by the compression in the coil spring 24, the cam 26 will start to climb up the surface of the recess 27. This not only allows the main body 12 to rotate about the axis of the shaft 18, but also to rise along the shaft. The vertical and swinging motion of the main body relative to the base ll and the ski causes the lugs 14 and 15 to take part in a similar move ment. Not only is the toe of the boot allowed to move sideways, but the lugs move upwardly away from the sole of the boot. The further the main body swings away from the centerline of the base 11 and of the ski, the higher the lugs are lifted. This reduces the friction between the boot and the ski and allows it to release. It permits the boot to release, irrespective of the condition of the ski binding elements and the boot; the presence of dirt and ice or a warped or split condition of the boot sole is not able to inhibit the releasing action. It can be seen that the simple, rugged construction leads to a long life of useful service, and it is easy to disassemble the binding for cleaning, adjustment, and repair.

It is obvious that minor changes may be made in the form and construction of the invention without departing from the material spirit thereof. It is not, however, desired to confine the invention to the exact form herein shown and described, but it is desired to include all such as properly come within the scope claimed.

The invention having been thus described, what is claimed as new and desired to secure by Letters Patent l. A ski binding, comprising a. a base adapted to be fastened to the uppersurface of a ski,

b. a pivot shaft extending vertically from the base,

c. a main body pivotally mounted on the shaft and having a rearwardly-directed lug adapted in an operative position to engage the sole of a ski boot, the shaft extending through and rotatable in a bore in the main body, a counterbore extending downwardly from the top of the main body, a screw member fitting snugly into the counterbore and threadedly engaged with the upper end of the shaft, and a coil spring lying in the counterbore concentrically of the shaft and compressed between the screw member and the bottom of the counterbore, and

d. an elongated V-shaped cam and a cam contact area opposing the cam, disposed between the base and the main body and extending radially of the pivot shaft, the contact area including a V-shaped groove whose cross-section is complemental to that of the cam, the V-shapes subtending an acute angle, and a planar surface perpendicular to the shaft, the groove and the surface of the contact area being positioned with respect to the shaft, so that, as the body is rotated with respect to the base, the cam at times engages the groove with planar contact and at other times engages the surface of the contact area, the cam and groove constituting the only release mechanism of the binding.

2. A ski binding as recited in claim 1, wherein the V- shaped cam extends downwardly from and is rigidly positioned on the main body and resides in the groove which is formed in the base.

3. A ski binding as-recited in claim 1, wherein the vertex of the cam is located in a plane passing through the axis of the pivot shaft and extending lengthwise of the binding.

4. A ski binding as recited in claim 1, wherein the cam exists in two sections located on diametricallyopposite sides of the shaft, each provided with a groove in the base, one cam-and-groove extending forwardly of the shaft and the other extending rearwardly.

5. A ski binding as recited in claim 1, wherein the lug is slidably mounted in the rear portion of the main body and wherein a screw is mounted in the main body and engages the lug to provide for vertical adjustment of the lug relative to the main body. 

1. A ski binding, comprising a. a base adapted to be fastened to the upper surface of a ski, b. a pivot shaft extending vertically from the base, c. a main body pivotally mounted on the shaft and having a rearwardly-directed lug adapted in an operative position to engage the sole of a ski boot, the shaft extending through and rotatable in a bore in the main body, a counterbore extending downwardly from the top of the main body, a screw member fitting snugly into the counterbore and threadedly engaged with the upper end of the shaft, and a coil spring lying in the counterbore concentrically of the shaft and compressed between the screw member and the bottom of the counterbore, and d. an elongated V-shaped cam and a cam contact area opposing the cam, disposed between the base and the main body and extending radially of the pivot shaft, the contact area including a Vshaped groove whose cross-section is complemental to that of the cam, the V-shapes subtending an acute angle, and a planar surface perpendicular to the shaft, the groove and the surface of the contact area being positioned with respect to the shaft, so that, as the body is rotated with respect to the base, the cam at times engages the groove with planar contact and at other times engages the surface of the contact area, the cam and groove constituting the only release mechanism of the binding.
 2. A ski binding as recited in claim 1, wherein the V-shaped cam extends downwardly from and is rigidly positioned on the main body and resides in the groove which is formed in the base.
 3. A ski binding as recited in claim 1, wherein the vertex of the cam is located in a plane passing through the axis of the pivot shaft and extending lengthwise of the binding.
 4. A ski binding as recited in claim 1, wherein the cam exists in two sections located on diametrically-opposite sides of the shaft, each provided with a groove in the base, one cam-and-groove extending forwardly of the shaft and the other extending rearwardly.
 5. A ski binding as recited in claim 1, wherein the lug is slidably mounted in the rear portion of the main body and wherein a screw is mounted in the main body and engages the lug to provide for vertical adjustment of the lug relative to the main body. 